Well, I'm more confused than ever. I was curious as to the AFR table directly effecting fueling, so I made two maps. On the first I added 5% (using the F trim table) to both the F & L tables. On the second, I left the F&L tables as they were and plugged this:
afr rich map.png

into the AFR map. Previously this was mostly 14.5:1.

I then ran both at idle and 2000 RPM. The map where I adjusted the F&L tables was richer than the original. The one with the adjusted AFR table wasn't.

So WTF DOES the AFR table do? At this point I'm totally confused. I was going to do a bunch of calculations to try and put a unit to the F tables, but now I'm not sure I care anymore. I think I'll just adjust the F tables to get the fuelling where it needs to be and not worry about what it all means.
 
Last edited:
Did you ride it after the AF table change? Did you turn O2 off? What is the F/L switch settings in your tune? The AR table is ignored when the data is outside of the narrow band O2 sensor.

The WTF table is a new to me. Must be a one of those hidden tables.:):)
 
Did you ride it after the AF table change? Did you turn O2 off? What is the F/L switch settings in your tune? The AR table is ignored when the data is outside of the narrow band O2 sensor.

The WTF table is a new to me. Must be a one of those hidden tables.:):)

No, 60 mph winds here today and 35 degrees. Yes 02 sensor is off, only 1 bung in the exhaust. F-L table is at 0 above 1300 RPM, which is why i tried both idle and 2000 RPM.

so maybe the afr table just gets ignored if the O2 sensor is disabled. I could see that, but i still don't understand why you can put different ratios in there if the computer just ignores anything other than 14.5

I often find myself running on the wtf table lol.
 
Keep this in mind, TuneECU is only an interface to interpret data, the actual numerical values are not important in the table. When adjusting the table directly you'll hit a point where it won't go any higher, 17 or 18 thousand. At that point you can force it higher by adjusting the enrichment table and applying it to the F table.

The generally accepted method of tuning with it to simply ignore the AFR table if the O2 sensor is off and tune using the fuel table. With the F/L switch low like that, it makes fueling adjustments easy, tube idle with L table, tune everything else with F table.

While there is some level of L table referencing going on over 1300, it's incredibly minor once the F/L threshold is exceeded and your in pure F table territory.

I stopped tuning with MAP/L-table/Vacuum because a small 3% TPS difference can swing you from 650hpa to 900hpa on the R3 because of the engines design. When the engine pulls maxed out hpa readings at 2200 RPM and 8% throttle everything from 9%-100% is the same MAP signal because it's already saturates. As a result, there is some F table referencing at all RPM, there has to be for the bike to run. Since we're not privy to that formula, trial and error is the only way to adjust it...or, just force full F table usage, problem solved.

If your trying to estimate a map, say, after adding a Rotax so you can ride the bike to the Dyno there are two way you can do this. Calculate the increased air mass and add fuel to compensate, or, take your current torque curve and your expected torque curve Delta % and add it to the table, then pad the table by 5%.

Both will be off because of VE changes, but, I've done this 3 times now, and all 3 times I ended up on the rich side of 13:1, so safe, but rich. Good enough to get to a Dyno.
 
Last edited:
I do, however, stand by my advisory that best performance is achieved with it OFF using a dialed in Dyno tune for your bike.

100% behind you Rob...to my way of thinking at least. I havn't had any experience with tunes so i installed PCV and had my bike dyno tuned by race bike technicians. I have done this on my last 3 bikes, a Triumph Storm and my two R3 Roadsters, as well as my cobbers Storm. Each time we have been very happy with the results. I found that the tune in my 14 Roadster was way different in my 16 Roadster!...same bike, different hearts...i'm sure they beat a slightly different pulse even tho they have the same motor. For this reason, i have come to the conclusion its best to have your bike individually tuned...i could be wrong because i have been wrong once b4 in my life!..just sayin...
Ohh, and happy new year Rob..you been layin low...so its good to see you back.
 
I'm revisiting some of this stuff and came across this YouTube where the guy is smoothing out the fuel tables (starting at 4:10). Does this guy know what he's doing? Hoping some of the experts will chime in.

 
Ok what that guy is doing is uh... Blind guessing.

An engine does not flow air in a linear manner across the rpm and throttle position. It also doesn't burn the same rate across RPM, depending on ignition map.

While a smooth linear tune does have merit, it's mostly as a predictable base tune to be dialed in using a PC-V.

Adjusting the fueling without any sensor feedback, is dangerous and frankly, it's really stupid for a non-pro.

Could Neville or Nels blindly write a base tune for an engine they've built/know, probably, but even then it's going to need sensor feedback to be correct.

The spikes in the curve can be required based on intake and exhaust pulse tuning, timing map, F-L transition, non-linear throttle cam, secondary throttle opening position, etc.

Q: How can you blindly know the % difference required without objective test data?

A: You can't.

The test data can be 1/4 mile times, time from one speed to another, wideband O2, 4 gas analyzer, almost anything repeatable, however you NEED some sort of feedback from the engine.

My opinion only, people are always welcome to trash their bikes to their hearts content.
 
Last edited:
Ok what that guy is doing is uh... Blind guessing.

An engine does not flow air in a linear manner across the rpm and throttle position. It also doesn't burn the same rate across RPM, depending on ignition map.

While a smooth linear tune does have merit, it's mostly as a predictable base tune to be dialed in using a PC-V.

Adjusting the fueling without any sensor feedback, is dangerous and frankly, it's really stupid for a non-pro.

Could Neville or Nels blindly write a base tune for an engine they've built/know, probably, but even then it's going to need sensor feedback to be correct.

The spikes in the curve can be required based on intake and exhaust pulse tuning, timing map, F-L transition, non-linear throttle cam, secondary throttle opening position, etc.

Q: How can you blindly know the % difference required without objective test data?

A: You can't.

The test data can be 1/4 mile times, time from one speed to another, wideband O2, 4 gas analyzer, almost anything repeatable, however you NEED some sort of feedback from the engine.

My opinion only, people are always welcome to trash their bikes to their hearts content.

I figured as much and I have no doubt now that it has been confirmed by a true authority. Thanks @Claviger
 
Here is a screen shot of my F table. You'll notice compared to most R3 maps, its WAY more linear, the reason is two fold. First, my bike builds power quite differently to a stock engine bike, so the airflow increase is actually much closer to linear. Second, a nice linear map like this makes the PC-V table much more intuitive to build while on the Dyno and saves a huge amount of time. It also prevents a situation where a three cells can be fighting each other in the PC-V. For example, if a non-linear TuneECU map cause three cells near each other in PC-V to be: +20 // -10 // +20, the PC-V gets a bit wonky and starts averaging values you don't want it to.

Map Screenshot.jpg
 
Back
Top